Method of and system for eliminating fading



June 27, 1933. J H H vnv o xug JR 1,915,782

METHOD OF AND SYSTEM FOR ELIMINATING FADING Filed June 11, 1926 I 4 Sheets-Sheet l Q I I I k u f V g} v n H) N N @5 v Q) k a E E avwemtoz N JOHN HAYS HAMMOND JR. i 7 D @5 ms Qbtom%}(idw June 27, 1933. J. H. HAMMOND, JR

METHOD OF AND SYSTEM FOR ELIMINATING FADING Filed .June 11. 1925 4 Sheets-Sheet a MMMHMM JOHN HAYS HAMMOND JR.

June 27, 1933. J. H. HAMMOND, JR 1,915,782

METHOD OF AND SYSTEM FOR ELIMINATING FADING Filed June 11, 1926 4 Sheets-Sheet 3 /RESULTANT EQUIVALENT R ANTENNA as i; E W\ l /E WE anoeutoz I JOHN HAYS HAMMOND JR.

332th WWW 244W June 27, 1933. J. H. HAMMOND, JR 1,915,782

METHOD OF AND SYSTEM FORELIMINATING FADING Filed June 11, 1926 4 Sheets-:Sheet 4 mil Him

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awuewto'c JOHN HAYS HAMMOND JR 85 h wj m} m Patented .lunel27, p

F'STZTE sonnnnszsiiminvioivn, 5a., or 'c-roeonsrnn,iivinssaoiiusn'r'iis unrnonlor AND SYSTEM son. ELilliINATING- FAD-ING Application filed June 11,

1 This invention relates .generally to radio therefrom, together with varying conditions of the upper atmosphere, determine. the-occurrenceand location of localities of weal;

and strong signal reception duri'ng fading periods. 1 Thus a vertical wire antenna may give at any given'instant of'tim'ea fading pattern with the weakspots at certain loca- .tionsywhereasif the antenna were tilted to a diiferent angle the fadingpattern at that thesame location. V s

As is Well known, during a period of trans mission;at any given point sufficiently, remote froma transmitter, tliereceived signals-may be strong for a period oftime and then become gradually weakened until they almost or completely disappear. At a later ,1 The present invention approximately to a frequency-offading. of

time, the signals will increase" and finally build-up to as large a value as befor'je the diminishing occurred. The period of fading and strengthening of signals may be of theorder. of a minute or'two corresponding cycle per second.

minimizing of v fading by periodically and continuously altering the tilt of the antenna in any or alldirections and thereby altering 1 the tilt or angle of radiation'of the radiated wavesin such aman'ner that atany place radio energy will be availablefor signalling with fading intervals which" are small com 1 pared with the time required for sending a signal; Thus for radio telegraphy, tlie frek quency of fading-is made'fihigh' compared with the speed ofsending dots andfidashes andinay be of the order ofl,000 cycles. For radio telephony the frequency of fading is instant wouldnotrhave the weak spots in I 1926. Serial no. .iiaisv.

made high compared the highest' frequency of oscillationsused and in speech or music may be ofthe order of 20,000 cycles per second. Thus for telegraphy the rate of fading is made roughly, 100,000 times the original rate and for telephony roughly 2,000,000 times the original rate of .01 cycles per second. By this method every point" of reception will be covered by a strong point of the radiant ave at a frequency which will not be detrimental to the usual reception of signals and on the other hand will cause cer min-portions of the messages to penetrate whereas otherwise they would not.

Accordingly, by swinging the antenna backward and forward at high speed anyspot in the line of swing would be covered at least once during'every cycle" of tilt of the antennaland each s ot "therefore would receive energy at high frequency'rate rather than at the slow rate dependent on the con dition of the Heaviside layer as in present fading.

; It is an object of this inventionto perform the equivalent. of tilting the antenna electrically.

' 'lheva 'ious features of the inventionwill be apparent from the following description oftypical circuits illustrated in the accompanying drawings in which:

Fig.1 is a diagram of anassumed fading 'patternresulting from a vertical antenna at a given instant. '3

Fig. 2 is a similar diagram of a fading g pattern resulting from atiltedantenna. accoinolislies the v t 'ofa verticalantenna and means for tilting Fig. .3 represents an electrical equivalent it to and from a position. H 1 V t Fig. Eaisan illustrative diagram. Fig. 3b is a diagrammatic representation of are'ceiver; Y V Fig. 4 is a diagrammaticrepresentation of a transmitter having anelectrical equivalent substantially horizontal telephony; l 1 '1 -Figs. 5 and 6 are diagrams explanatory of the operation ofa further embodiment of myinvention. V Fig. 7 is a diagrammatic representation of of a continuously tilted antenna adapted for 7 I With a transmitting antenna ina vertical position as at. 1, Fig.1, the field strength due to this antenna may vary with distance substantially as shown withmaxima of intensity tat locations 3,5, 7, etc., and with minima of intensity, at'locations 2, 4c, 6, etc. The positions of maXima and minima of intensity I, are created by and are dependent on reflecv energy subject to little or no fading.

tions, interferences or retraction patterns due to phenomena'in the upper atmosphere, and the unsteadiness which causesqthe alterations of the intensity patterns resulting in "fading-may be consideredtobe caused by analteration in' the upper atmosphere. Thus tofproduce energy atpoints 2,4, 6, etc., with .none 21133, 5, .7, etc, it is' normally necessary to to-'waituntil'the alteration in the upper atmosphere has occurred which will incur this result; 'However, the. purpose of this invent-ion is to'cause energy to appear at 2,

'4, 6, etc. as wellas at 3, -5, 7, etc. by'tilting the wave front, that is, changing the angle of radiation'in'a manner such as would be accomplished byztiltiiig the antenna circuit as shown at 9-,Fi'g." 2. Thus, if the'tilting of the'wave front from position 1 to or through position t-l is accomplished 1,000 times per second the 'energyfwill be caused to'appear and disappear .at 'a-ny of the posi- 'tions2, 3, 5, 6,7, etcpat approximately '1',0O0ti1nes per second, during what-otherwisewould be a fading interval. e

. The equivalent of a tilting antenna, as shown, includes a vertical antenna combined with a horizontal antenna pointing in the direction'ofa location at which a signal is to be received and fading eliminatel. v

The apparatus involved in carrying out my invention for telegraphy is schematically shown inFig. v3. This comprises a vertical antenna "VG and a horizontal antenna NS pointing towarda point ofreception. Coils wand "11' "areprovided for the vertical 'antenna and 'coils12 and 13for the horizontal antenna by which they maybe excited with alternating current power of the radio frequency'to which theantenn'a systems are tuned. These coils may receive energy from.

onsil, 15*o'f a rotor which maybe turned to'cou-p'le witheither'set of antenna coils or in part with both. This rotor is'turned by a motor, for"ezrample,at 500 revolutions per second'so that each antenna is actuated l,000

. timesper second. The power source for actuating the antennais" alternator 18 or any other'source'of higlrfrequency energy which feeds energyto the slip'rings cfthe rotor by means of transformer '17. Key 16' is "for the'purpose or closing and opening the rotor the fIQtOI' 'COUPlGd. to'the vertical antenna the initial field is the same as due to vertical antenna 19-20, Fig. 3a. WVhen the rotor has turned an eighth revolution the initial field will be the same as due to an antenna, I

diate value four timesduring each revolu- I lllOIL' In consequence, a non-oscillating detector receiver of the usual type as exemplified by the circuit 24, Fig. 3?), will pick up For the purposes of radio telephony, it is seen that-the rate of tilting of the initial field must be of higher frequency than speech frequency so thatit becomes impractical to turn a rotor I at the required speed.- The strength of the currents in the antennae,-how ever, can be varied causing a tilt of the initialfield which will produce substantially the same effect as a tilt ofthe ai'iten'na. A transmitter for radio telephony inaccord-ance with this invention is shownin Fig. 4. V

In accordancewith this figure, the vertical antenna VG is actuated bycouplingfrom co1 l2 6 in the plate circuit of radio frequency amplifying vacuum tube 27, and the amount of current produced in' the antenna is rough ly proportional tothe voltage across condenser 28. Similarly, the horizontal antenna NS is'actuated'by coupling coil 29 in the plate circu'it'of radio frequency [amplifying tube 30 and the-amplitude of theradio'frequency oscillations is proportional to the voltage across condenser'31. '.-Grid voltage :for tubes 27 and 30' is supplied from coupling 32 to the oscillating circuit 33, 34 of-a vac uumvtube-oscillator '35, which generates a current of a frequencyto-which the two an- Tubes 36 and 37 with associated circuits are for the purpose of varying the'tilt of.

the waves by changing the relative magnitudes of the radio'frequency currents in the antennae as determined by the frequency of oscillation of tube 38 and associated circuits.

The couplings 39,40 of the grid circuitsof the tubes 36 and '37 to coil e 1 of the oscillatory circuit of tube 38 are such 'that the charges applied-to. the grids "of tubes '36 and 37' are of opposite phase, and as a result, when the plate-current through coil 41 is highest, the plate current through coil 42 is lowest, so that the voltages acrossxcondensers 2 8 and 31 pulsate, with the voltage on 28 highest when the'voltage'on3l is. lowest, and vice versa. Consequently, the radio frequency power developed by the tubes 27 and 30and impressed upon the verticalv and 1 (and is aminimum from theho'rizontal an-' tennaif Atfthis instant the radiation is at jawery small angle of tilt from the vertical;

I 'At the ther end of'the cycle, the horizontal V antennaaconiponent of the radiated energy is i ata' maximum and the vertical antenna component at a'minim'um, and the angle of tilt from the vertical islargeg In-th-is manner,

able at a 1'5:

' it is seen that the tilt of the waveis changed periodically, so that 'energy becomes availdistant point at a high frequencyratef' I p I The transmission of telephone messages is accomplished as usual by] modulating the radiated energy. For this,"modulator'tube 43 is provided with current from the battery or generator source 44 delivered'to the modulator tube 43 and the tubes 86, 37, 27 and 80, which are to be modulated'through, the com- I mon reactor 45, in the usual manner. When v the grid circuitof tube43 is suitably actuated at speechor other audio frequencies by.

7 means ofrmicrophone circuit/l6 or other source'of electrical audio frequency power,

voltage variations are".devel'oped 'across reactor 45- in the usual' way,-causing plate In'odulation does not in any manner influence the ratio of horizontal rad ation to Vertical modulation of the succeeding circuits This radiation from the antennae nor the angle of tilt of the radiated wave, which are governedsolely by the ioperationof circuits of tubes The radio telephone signals may be re ceived atadistant point by'theus'ual noninvolving a oscillating detector circuit, such," for examplefasis shown schematically in'Fig. I antenna 23, detector and indlcator 25. i

I fIt is to be understood that in reception with is any simpleantenna, a supersonic frequency component willbe' present in the received energy, corresponding with the frequency 'with the said ante'nna."

I I Therefore,;if desired, a system ofi double t hich' the rapidly. a g g e from becomes that required for optimum reception detection may-begused, involving tuning to the radio 'energy detecting to produce currents of intermediate frequency, or, frequency of tilt, amplifying, and-again dete'cting'to original audio frequency 'curproduce 'the frents.

The circuits shown Fig.3 and may .not eliminate fading in all directions. In

order toeliminat'efadingin all directions, an arrangement-may be used employing Lthree antennastructures', all operating at the'same 2 radio frequency and preferably intphase. This modification of the method isindicated Lschematically in Figs; 5 and 6,1" [W1th three manna NS," 'EW, and .GV as in Fig; 5, all

actuated in'phase or with 1 degrees opposition, therewill be aresultant plane polarized radiation as if from a single antenna, GR. It

phase or-180 outfof'phase inthe' high fre quency sense,";to avoid elliptically polarized radiations which result in directionaltrans-' mission. The direction GR of the resultant field is controlled by relative magnitudes of component radiations and can be'made to assume substantially all angles of tilt and OIIQIItEItlOII'bY varying the intensity of the component radiationsjby a double process.

For example, one process or step involving 7 thehorizontalantennae only, may make the combinedefiects of these two antennae by .themselves'produce a rotating field, with the resultant horizontal radiation swinging from 'west to south, to east and to north, etc), without change 'of intensity, The frequency of rotatlonmay be low compared with the radio frequency employed in radio transmission. This rotatlng horizontal field of unchanging resulting intensity when combined withthe vertical'field will produce a resultant due to all'antennze with a constant angle of tilt, say 45 degrees, but with the'orientation changing in accordance with the horizontal rotating field, making the tilt to'west, south, east and north, and all intermediate points in succes-' sion. In' addition to this circular rotation 'of'the field, a second process or step may is important that the antennae be excited in change the relative energies of'the horizontal and vertical fieldsso that all angles of tilt maybe attained, making the resultant field cover'all' directions of orientation and all angles of tilt, in a-time which is small-in comparison withthe period of the signal to be transmitted. This is shown inFig. 6.

For telegraphy thefrequency radiated may be of the order of 1,000,000 cycles, the fre- 'quency of rotation 20,000 cycles, and the fre quency of tilting 500 cycles. I For telephony,

however, the angle of tilt must be changedat .a much higherrrate, say 20,000fcycles per secend. This requires the rotation tobe made,

say at 100,000 cycles, for-a carrier frequency I of the order of 1,000,000 cycles. Modulation at the audio frequencyrate changes the intensities'of allgradiations in unison, so that the'rotation'of the field in space is not affected,b ut only the magnitude of the resultant field is changed in accordance with the, audio modulation. i I I i I v I Atransmitter of this type is shown in Fig. 7 which is primarily a radiotelephone trans- 1n'itter,- suitable for operating, into an ordi-fl lit nary typereceiverg It isarranged, however,

with keys and switches in'three places to per- ,mit telegraphy either by audio modulation,

by intermediate frequency modulatiomor'by" continuous wave telegraphy.

.iln'this transmitter, the following frequericies are arbitrarily assumed for-purposes of illustration and are as follows :The radio carriercfl'equency, 1i;O00,0QQcy-cles per-second, is, determined by the; frequency of gthe oscilla-i tions :producedfby tube'47 andeassociated cir;

, icuit-ssthe rate of rotation of thehorizontal associated circuits: the; frequency of tilt,

'QQQQQcycles, is determined by the frequency 7 of, oscillation oftube 49 and associated cirmcuits; Fortelephony the entirefradiationis;

modulated iii-accordance with speechor other audio sig lalsgenerated by microphone 50 and associated circuits, For audio telegraphy, the-microphone may. be replaced bythrow of i switch to cause the system to be modulated by electricalsource 51, say 500 cycles, and for dot: and dash by closure of key 52. Contin nous-v Wave signalling may be accomplished byekeying the circuit of radio master. oscillam tor l'ijbykey 53,- Whichds held closed for other types of communication. Forsuperraudible modulation, key 54: maybe used,

changi-ngthe rate of'tilt:f1.'on1;20,000 tel-0,000

cycles-,foriexample. This'latter key maybe zlfinornially open for other communication, butthis circuit may be keyedf'or-multiplex Work without; interfering with, radio telephony, or

a udioradio telegraphy. Ifva secrecy; ea ture isdesired, a Wobbler mechanism maybe 7 as applied to oscillatorytZ to-va ry the radio carrier frequency" to prevent continuous Wave reception when key '53 'is-clo'sed, Without, howi ever, -interfering with the operation of: the:

system a'sto quality of signalsi The three antenn'aeare vdriven from the out put: of three radio frequency. power and amplifiercircuits, the; vertical antenna- GV "fronr tube 55, the east-West antenna from tubes 56"and; 57, and north-south antenna,

from tubes 58 and;;59.=' Allof; these tubes areexcitedin the gridcircuit in uniso'n'from the outputrof masterradio-oscillator 4:7,, and

each grid" is providedwith-the customaryindividualcondenser and res stance for confrom anteni aeflNS and'EW and the'vertic'al antenna'VG is' altered in'accordance with r voltages'developd across coils 60 and G'l'by the action'o'f tube 62,{actuate diby master os-i Gunter 'tiib'e49. These' Voltages across 60 and '61 offrequency equal to the rate of tilt 20,000'cycles, areof, opposite phase so that. more power is-thrownto the vertical field by coil 61, at thesame time that; less power isth-rownzto the horizontal field by: coil 60 -;a11d

field, 100,000: cycles, is determined byztheefre-c queneyof oscillationof osc-illatortube 48 and vice versa. The entireradio frequencyvfield tiltedand rotated, may be modulated .;in]- tensity. Without, change directional relas tions means .ofz'v ariations in voltage dieveloped across, choke coil,63, such lvariations in voltage; being at audio frequencyyin accordance With'tele'phone or telegraph signals; im

pressed go n the grid of the modulator tubefih It, is gem from the above, description that the. tilting process issubstantially the same as inlllig. 4:, and thatthe-saine general method ofiinodulation: is used. The essential difier- 1 once isthat instead of exciting a singlei'horir.

zontal antennalby tube 300i Figf t, two horizontal'antennae, are excited'in such a manner as totproduc e aL-rotating field, in. the ,horilontal plane; through the operation of. tubes. 48,. 56,157, ,58, :59, andjthe tube 65 and as-v sociated circuitsi v a The operation to produce this field is as follows lube 65 is actuated in the grid circuit from. master tube 4510f 100,000 cycles frequency, and in. the plate; circuit direct voltage, ex! cept. as modulated at the lower frequencies. For the present, we L m ay consider the plate.

circuit supply to be steady, with, tubes 62,.and

(A not operative, that, is without any. grid,

encitatioir.v As a,result,',the tube 65 produces output power 016 100,000 cycle frequency. Thi'spower actuates primaries 66 and, 67,015 transformers which supply. the amplifiers 56, 57, and 58, 5 9 Wltllplate power. But i the circuits are-so adjusted by resistors 68, 69

and condenser 70 that the current,- to trans- 1 former 66 is degrees differentin phasefrom:

the currentlto transformer 67. NoW -the; circuits oii t11bes- ,56 -and 57 are of a typewhich" give amodulated output in the antenna,EW

with carrier aye suppressed,-accomplished 1n part'by reyersingthe coils 71,72, relatiYely, to each other; Similarly, the tubes 58;;and59e give ainodulated output in theantenna NS with carrienwavesuppressed, v Butrthe-ph ase 0f he modulation forithe currents 'of th two antennaae QIHQFSbYZQOLlGgI GGS in time,

and tneantennae themselves, are located 90'. degreesapart' inf spacez' Accordingly, it isreadily seen that the resultant of, thetwo,

latory high frequency field of constant mag} nitude, but rotatingataqfrequency of revolus than equal, to the frequency ofcurrents, of the I supply circuits; 66;an d 6 7., 1

For, let the Wave form for fieldldueto the;

N S antenna (Fig. 7) be given by- )Fi Ffl/isin pz's'i'niwz in which A aconstant, 'p is an angular Vei locity corresponding to the rate of'modulai tion (100,000 cycles) and. m an angular Veloeity corresponding: 'tthecarrier frequency,

j( 1,00@,0003 cycles) lhen, because ot the equal; Voltages,

145 v, e, I the vertical antennae; The resultais readily tubes, and equal-antennae for the two hori- Q, antenna'fvvillbe e 1 7 V raeaf nyon o 'rsi i fijw a oifl invvhich ltgand 95 are constant'phase angles.

splitting,device, d p= 90 and the west 'eastr "field becomes, "ons implifying By combining thel effectsf of thetvv o cornpone'ntfields, by: a vector additioniinspace,

I i v we 'find'vthe numerical resultant of thejt assass ns anjunin cluliatdl fieldf tand I plitude A. QMoreover, the-direction of the l P irtha is,

field is, given readily :by thefii 'gle s vv hi ch the resultant field Thatisitheanglefifi with angular velocityppso'that theresultant field traverses, alljpoints of the compass 100,000 times per second, andth is I fonsti'tutes the rotating field constan magnitl ide, v in ifthef horizont-al plane.

'As is;

'vidd for; var in theftiltof the. aves; by

'Ya I- -"P z esteem sistsfin cycli a y a y n le r ia-' and vertical antenna Q Fig this is done U V bytiib eQGQ and;associated circuitsg 'Which developsvoltage c ossgeoneo for,the.hori-' across 1, inductively l-coup'ledl to @051 6030i seen to produce: a: variation "of theitilt 'otthe wave fro'rnjsubstantially vertical to substantially horizontalposition. At a distant point in :"any ,direcjtipn energy will .be made available, gwh'en i;. sub]'ected "to detection-".x vill produce currents corresponding to the audio .rn'o'dulation. 1 i

s reception can 'fbelusedf the speech or audio signals directly after the first detection, or if desiredv after first detection, amplifying and second" detect-ion Eurv ther, if the key 54 is 'actuatecLchangingthe.

frequencyof tilting, these keyings may be used for telegraph purposes, withoutinter fe1iing=with telephony or audio telegraphy. 1 Or continuous Wave telegraphy'by its'elfmay J be accomplished by keying circuit t' 3,x jsince .this arrangement makes theqcarrier vvave available at all'points ithout it'ading as; Iwell V n n V l as the side waves a zontal antennzethfield due'to-thevvest-east amounts-oten'ergy su'pplied'to the respective; 90 V of eliminating fading in 1 ;--'the reception of radiantene'rgy which con jan'tennae; v

F; makes with h east e'c- 4.1, The method 1.1 w antennae." 1g. 4, so 1n F g. 7, means are proprocesses I" 7 a i Having I .fullyt and clearly described the principles involved in myinvention I claim:

1-.-,1he method of eliminatingfading inthe reception of; radiant energy which: in-

:lc'ludes :the step; of continuously electrically varying the angle of tilt from vertical of theiefl ective transmittingantenna from and toward a substantially-vertical -position,*dur'- ,jing radiationof the energy. i

5, LThe method or eliminatin sdsg in V the reception 'ofradiant energywhich con- 'sists in transmittingenergy from adjacent :fsubstantially vertical-and substantially hori- V zontal antennae and varying cyclically' the produced by the modulation am'ountsof energy. supplied to'the' respective I antennae.- v v a g 3. The method of eliminating fading in the reception of radiantenergy Whichcon i 'sistsin transmitting energyifro n adjacent substantially verticaliand substantially horizontal antennae and varying inversely Y the .1 sists initransrnitting energy from adjacent 'substantiallyiverti'cal and'substantially hori-- zontal antennae and'supplying energyxto the antennae in a manner such that at alternating l-tirnes-the energy is iinpres'sedalm'ost exclusively on i'the Vertical antennaandgthe hori- 7 -zontal antenna respectively-and during the "intervening. periods impressing inversely varying amounts of energy upon the respective 5 .The 1 method tion of; th'e' 'transmitted energy at a-superaudible frequency loyv'er than the carrierfrea e v. quencv. Ema-antennae out phase Wlth the-millage 'i6. 'The"me th0dof ellmlnatlng fading m 1 i eludes-- the steps ofcyclically varyingthe vertic'a'langleofradiation of-the transmitted enthe' reception: of radiant energy which in-' 1 y or eliminating fading in the; reception of radiantenergy which conergy and transmitting on a continuouslyrov .1 The Inethod' lof eliminating 'fading in the Teceptionbf radiant energy which con-' each'lother" causing-said horizontal antennae 'tofprod-uce a rotating field and electrically mi in tiltingthe'angle efradiation of the transthe vertical and horizontal antennae; a 83Method of eliminating fadlngm the re- "cep'tion ofradiantenergy which consists in transmitting energy from ad acent substanimitted energy between limits determined by tially' vertical and: substantially horizontal antenna systems; causing said horizontal antenna system to produce a rotating field and 45;i n cyclically varying;proportions;j, I 13-rA msmitt ri onraoliant energy- .supplying'energy to thetwo antennasystems I I {co1npri's1ng means forgeneratingcontinuous in a manner such that ata lternati ngtim'es e :therenergy :1s in pressed substantially exclu- I sively. on "one system-and; the othersystem r'e -5 spectively and iduiing ;rtlie' intervening 'pe-' --t'riods impressing inversely varying amounts ofrenergy upon-therespe'ctlve antenna syscomprising means for .generatin g i continuous electrical oscillations, a "substantially wer- -t1cal antenna-,1absubstantially, horizontal anztenna andsn'ieans' for impressing said 0scillatlons ;Zup.on.-':the respective antennae 1n cyclicallyvaryingarnounts; I

5 10. A; transmitter for: radiantenergy comfprising means for generating continuous .electrical oscillations, i a substantially -'\ver- 5' .ticalla'ntenna;asubstantially horizontal-an- .o tenna fllld lliQlIlS for impressin'gisaid osfcil FlationssubstantiallyalternativelyJon:'said an "atennae eta-predetermined freqnencyf i' Ill. :A' transmitter, for radiant energy. en-

f "-1 'abling energy to be received 'Withoutifading, gconipilsing.meanszfor generating continuous ;9l0tijlcfllLOSQlllEll310I1S .assubstanhally ve'rtiealantenna, a substantiallyahorizontal. an :tenna' andameans for causing said oscillations 3130- to be impressed at difi'erent 1 times substantially exclusively on :the trespectiveiantennae electrical oscillations,a substantiallyrrvertical antenna; a substantiallyhorizontalantenna,

jons upgm tlie antenna' andimfeans for .lrzrrrg-glectrical oscillations :of a frequency ifi r n f omth thje rstzmentidndos- 'cillations to cause the first mentioned ,osoillatrons-to? mp jssed; uponatl'ietwoiantennee er zo it ia 6 950 193 1 ten amea for' mp e si gsa I c l tions ,on 1' t e ,r'ant l na and: me n z' r v v cyclically varying I the proportion :of j said o scillations impressed s upon the respective e tubegoscillator forp rodu cing os 'cillations of. d'ilferent frequencyJ-from T-thfat 0f *the first mentionedgoscillations, and -three I electrode control tuloes';inserted in the sup ply. circuits "of the antennae respectivelyand l havingxtheir grids connected: to. "the 1 output 'circuit'of; the vacuum tube oscillatorl so asito icauselthem'to' besimnltaneously,charged in opposite sens'es; I

" transmitter rroadiant energyren of a signal Wave and varyingth I it tale ctricalenerg rflfil lr- ';and;tocauseenergytobe-lmpressednponsaid i V I antennaeat the, intermediate 12.; A; 4 transmitter*fonradiantenergy coin-- pris ng; means- I for ;-generat1ngacont nuousr {and means.;.for.fcau sing said last mentioned -,osc1llat1on 'to inverselyf and continuously electrical oscillations; a substantially verticalgantenna and a substantially horizontal antenna arranged at right angles to each'l sother, means ltojr impressingsaid oscillations ;;upon -the respective; antennae and means for o 1 or f I I I I JtllfiT-iHg thEWZLVB front of the transmitteden-. I i "93A transmitter'for =ra'diant energyfem- 7 'iabling energytobe receiy'edawithout fading,

Margy.

' antenna, a pluralityotsubstantially horizontal antennae, meansv for impressing sa d oscillationsupon the antenna means for cans- 1 .ing' the .1horizontal. antennae to ,produce a r0 il i ilngfield. and means :for cyclically varying fthepyertical.angle,of radiations of; the transmitted energy. I y I 16,, The method of radio transmission? iavhiehcomprises,"continuously; and cyclically varying the Vertical angle of the Wave front -e'rgyjtrans1nitted to send a signal.

which comprises; transmitting energy from adjacent substantially verticalqandsubstan- 18, A transmitterfor radiai'itenergy comprising, ja source or high requency-oscillaonsif a plurality of antennae arranged at. ang-g es t ifea hother, means f r impr ssing said high frequency energy f'up'on" said antennae,

.s ignal means .jiorI modulating-the energy "transmitted, through said antennae; :a source of lower superson c frequency oscillatlons e total V V V 17'." The method of radio .trahsr'nissiion vary the proportion (ifsaid modulated high 7 frequency energy traIiS mitted by eachlof said antennae and thereby continuously vary the angle oi the resultant'ivva've front transmittedby said antennae," I I v I I 191 A method of eliminating fajdingin the reception of radiant energy which consists in I transmitting I energy from adjacent sub- 'z ontal [antennaawvarying inversely the Se'naa11 vea1ca1 I and} substantially 'hori 1115 amsunts of energy supplied to'the res'pective antennaeand varying the nature of theitotal r jg-"x me *f2O. The method of eliminating fadi'n'g'in thereception qfradiant energy which com- I I electrical -energy forthe purpose of'signal- "l stn nt q ed vmeansii ncl-ud a I vprises,cyclicallyvarying the angle of radia- "tion-o'f the transmitted energy at a superaudible'frequency lower than the carrier frequency and- -varying the nature of the total transmittedenergy for the purpose of sig- I "-12 1. A tranSmitter for radiantenergy enabling energy to be receive'drwithoutfading,

23. A transmitter comprising means for generating continuous electrical osc1llat1ons,.a substantially, vertlcal antenna and a substantially horizontal an tenna arranged at right angles to each other,

means for impressing said oscillations-upon;

the. respective antennae, means for tilting the wave front of the transmitted energy, and ymeansfor varying the total'transmitted enorgy to send a signal. v I r V U 24, 'A transmitter for radiantener gy comprising means for generating continuous electrical oscillations, a substantially vertical antenna, a pluralitysubstantially horizontal antennae, means for impressing said oscillations upon the antennae means for'causing the horizontal antennae to produce a rotating field, means for cyclically varying the vertical-angleof radiations of the transmitted en ergy, and means for varying the, total elec-I trical energy transmittedto send a signal,

25. In combination a radiating system, means for changing the vertical directional radiating properties of said system cyclically and ina continuous manner at a speedwhich is comparable with the signalling speed, and

means for varying the nature of the total electrical energy transmitted bythe said 'radieting system for the purposesof signalling, 26. Radio transm ssion apparatus compris 'ing a plurality of antennae having ditl'erently directional character stics, means to radiate signalling energy from each of said antennae successively, means to continually change the distribution of signalling energy to said an tennae, an electron tube amplifier networl; for

, each antenna and an electron tube oscillator common to the several networks. 3 V r 27. The method of radio transmission from aplurality of antennae, at least one of which is non-directional, which comprises generating signalling energy of carrier-wave-frequency,.impres sing said energy successively upon each of said antennae, and cyclically changing'th'e energy radiated from said antennae sothat each signallingimpulse shall V v for radiant energy en-j ablingenergy'to be received without fading,

two ofsaid'aiitennae. I V I 28,-The method of overcoming fading in radio transmission from a pair of antennae,

each of saidantennze being energized through its respective electron tube amplifier network, which comprises generating signall ngenergy- J of; carrier-wave frequency, excit ng the net- 'comprise successive radiation from at least work of one antenna fromhalf-cycles of one polarity of a single phase alternating current and'exciting the network of the other antenna from oppositely polarized half-cycles of said 7 single phase alternating current thereby radiating the signalling energy from the two said antennae successively.

29. A radio transmission system compris ing a single highfrequency electron tube oscillator, a power amplifier system connected with said oscillator said power amplifier system having a plurality of independent'out- .put circuitsand separate antennae connected with said output circuits for the radiation of signalling energy, and means for effecting radiation first on one antenna and then on the mined timed relation.

other antenna in successive order in predeter- 30. A radio transmission systeincompris ing an electron tube oscillatorfcircuit,an amplification system comprising a plurality of power amplifier tubes each having input and outputcircuits with the input circuits thereof connected with the outputcircuit of said oscillator circuit, a separate antenna having difierent radiation characteristics independ :cuits of said power amplifier, and means ently coupled with each ofsaid outputcirconnected with said output circuits 7 for alternately effectlng radiatlon on eachof said antennae in successive periods, the

. r adiation of energy from one antennae being displaced with respect to the radiation ofenergy from another ofthe separate antennae. I

1 Y 31.. A high frequency transmission system comprising a pluralityof antennae of di'iierent "characteristicsat least one of which is nondi rectional, an oscillator for supplying current of the same-frequency to said antennae, and an amplifier for cyclically Varyingthe' impression of amplified energy from said oscillator to said antennae.

32. A high frequency transmission system' inaccordance with claim 31in which said amplifier comprises a plurality of vacuum tubes, and a source of alternating current for E;

rendering said tubes alternatively-effective.

533. The method'of 'overcoming'fading in the radio transmission of signalling energy from two antenna networks which comprises generating a high frequency carrier current, generating a second alternating current of different frequency, impressing said high frequency carrier current successively upon each of said' networks,"a nd" transferring the radiation effect from one antenna to another iao 

